What is E557?

Complete guide to understanding E557 (Iron Oxide Red) — approved in EU but banned for food in USA, with incomplete safety assessment and major international regulatory divergence

🚨 MAJOR INTERNATIONAL REGULATORY CONFLICT – APPROVED EU BUT BANNED USA: E557 (Iron Oxide Red) is officially approved as a food colorant in the EU. However, the FDA explicitly BANS red iron oxide from food use in the United States, stating it is “not FDA-approved for food use” and “not included in the FDA’s list of color additives approved for direct addition to foods.” Additionally, EFSA’s re-evaluation is incomplete; the authority has requested additional genotoxicity and subchronic toxicity testing. This fundamental disagreement between regulatory agencies about whether E557 is safe for human food consumption represents a significant regulatory uncertainty.

The Quick Answer

E557 (Iron Oxide Red) is a red food colorant approved in the EU but BANNED FROM FOOD USE by the FDA, with incomplete EFSA assessment and major international regulatory disagreement about its food safety.

What makes E557 uniquely problematic: E557 represents perhaps the most striking example of international regulatory divergence in food safety. The same substance — iron oxide red — is officially approved for food coloring in the European Union but completely banned from human food consumption in the United States. Why? The FDA considers it unsafe for ingestion, citing concerns about inhalation risks during processing, potential heavy metal contamination, and the availability of safer alternatives. Meanwhile, EFSA approved it for food use, though its re-evaluation remains incomplete with requests for additional genotoxicity and toxicity testing. The JECFA temporary ADI from 1979 has never been formalized 46 years later. E557 exemplifies how the same substance can be deemed safe in one regulatory system and unsafe in another — suggesting fundamental assessment gaps exist.

E557 is approved in EU but banned in USA — a striking example of regulatory divergence.

📌 Quick Facts

Chemical Name: Iron Oxide Red; Ferric Oxide; Anhydrous iron (III) oxide
Type: Red food colorant; food additive; inorganic compound
Chemical formula: Fe₂O₃ (ferric oxide anhydrous)
CAS Number: 1309-37-1
Color Index: CI Pigment Red 101 and 102
Found in: Candies, supplements, tablet/capsule coatings (outside USA)
EU Status: Approved; re-evaluation ongoing with additional data requested
FDA Status: BANNED for food use (approved only for cosmetics/external use)
CRITICAL DIFFERENCE: Opposite regulatory conclusions: EU approved, USA banned
Safety assessment: Incomplete in EU; JECFA ADI temporary since 1979

What Exactly Is It?

E557 is iron oxide red, a synthetic red pigment used as a food colorant — 100% synthetic, manufactured through thermal decomposition of iron compounds.

Chemical composition: Fe₂O₃ (ferric oxide anhydrous)

Appearance: Red to reddish-brown fine powder; odorless

Manufacturing process: Heating and decomposing iron salts (ferrous sulfate), followed by washing, filtering, and drying to produce fine powder

Key properties:

– Red coloring: provides stable red pigmentation
– Fade-resistant: does not fade during storage
– Thermally stable: survives food processing temperatures
– Water-insoluble: remains as fine particles in products
– pH stable: maintains color across pH ranges
– Low bioavailability: minimal absorption in digestive system
– 100% synthetic: not a natural mineral; manufactured substance
– Iron-based: natural iron oxide, but chemically synthesized

🔬 Understanding E557’s Nature: E557 is one of three iron oxide food colorants (E172 group: black 172(i), red 172(ii), yellow 172(iii)). Unlike E551 (silicon dioxide) which is completely inorganic or E554/E555/E556 which contain aluminum, E557 is pure iron oxide. Iron itself is a nutrient; however, iron oxide red’s safety for food ingestion is what divides regulatory agencies.

Where You’ll Find E557

E557 (Iron Oxide Red / E172(ii)) is found in candies, supplements, and tablet coatings outside the USA. It’s ABSENT from USA food products due to FDA ban.

Product Category	Application (Outside USA)	Frequency	Regulatory Status
Candies and confectionery (PRIMARY)	Red color	Very common	APPROVED EU; BANNED USA
Food supplements and vitamins	Red color/coating	Common	APPROVED EU; BANNED USA
Tablet and capsule coatings (pharmaceutical)	Red coating	Very common	APPROVED (external use)
Certain dairy products	Red coloring	Limited	APPROVED EU; BANNED USA
Powdered food ingredients	Red color	Limited	APPROVED EU; BANNED USA

Key difference from aluminum additives: While E554, E555, E556 are approved globally with varying safety concerns, E557 is fundamentally split: approved in EU but explicitly banned in USA. This is an unusual regulatory divergence.

The Critical Regulatory Conflict: EU Approved vs. FDA Banned

The most important finding: opposing regulatory conclusions on E557 safety.

FDA Position: BANNED FROM FOOD

Official FDA Status:

“Red Iron Oxide is NOT FDA-approved for food use.”

Regulatory citation: 21 CFR 73.2250 — “Iron oxides are certified for external drug and cosmetic uses only.”

Official FDA conclusion: Red iron oxide is “not included in the FDA’s list of color additives approved for direct addition to foods.” Using it in edible products “violates current U.S. food safety regulations.”

Why FDA banned red iron oxide from food:

– Inhalation risks during processing: Powder form presents occupational hazard to workers
– Potential heavy metal contamination: If not properly purified, can contain contaminants
– Safer alternatives exist: FDA prefers naturally-derived colorants with better safety profiles
– Conservative approach: FDA applies stricter standards than EU for food colorant approval
– FDA statement: “While Red Iron Oxide itself is considered non-toxic in small amounts, the FDA has not deemed it safe for ingestion.”

FDA-approved uses (external only):
– Lipsticks and lip products
– Cosmetic foundations and blush
– Decorative cosmetics
– Pharmaceutical tablet and capsule coatings (non-ingested coatings)

FDA does NOT approve for:
– Direct food coloring
– Oral medications
– Any use where it will be ingested

EU Position: APPROVED FOR FOOD

Official EU Status:

E557 (Iron Oxide Red) is approved as part of E172 (iron oxides group) under Commission Regulation 1333/2008.

Current authorization: Permitted in candies, supplements, various processed foods with maximum levels defined by food category

Why EU approved red iron oxide:

– Considered safe based on available toxicological data
– Low bioavailability (minimal absorption)
– Low acute toxicity
– Iron is a nutrient; iron oxide sources are regulated separately
– Traditional use history

EFSA ongoing re-evaluation request: EFSA has explicitly requested additional safety data, indicating approval is not final or complete.

🚨 REGULATORY PARADOX: The same substance (iron oxide red) is simultaneously:
– BANNED in USA: FDA explicitly prohibits food use
– APPROVED in EU: Permitted for food coloring
– INCOMPLETE in both: JECFA ADI temporary since 1979; EFSA requesting more dataThis fundamental disagreement between regulatory agencies on the same substance is unusual and reveals significant assessment gaps.

EFSA Incomplete Re-evaluation: What’s Missing?

EFSA’s current status: Re-evaluation ongoing with explicit data gaps identified.

EFSA has specifically requested additional safety testing for red iron oxide (E172(ii)):

1. In vivo genotoxicity testing at the site of contact (gastrointestinal tract)

2. Subchronic toxicity studies (longer-term safety testing)

EFSA explicit statement: “The Panel noted that concentration data on yellow iron oxide, red iron oxide and black iron oxide alone would be needed.”

What this means: EFSA cannot complete its assessment without more testing. The current approval is based on incomplete data.

⚠️ DATA GAPS: EFSA has explicitly requested genotoxicity and toxicity testing that has not been completed. The re-evaluation cannot be finalized until this data is available. E557 remains approved despite incomplete safety assessment.

JECFA Assessment: Temporary Status Since 1979

International assessment status: Still provisional after 46 years.

JECFA 1979 evaluation:

– ADI established: 0-0.5 mg/kg body weight
– Status: “NOT SPECIFIED (TEMPORARY)”
– Acute oral toxicity: >10 g/kg (very low)
– Meeting: 23rd JECFA session
– Updated 1984, 1989, 2002 with specifications added

Critical finding: Despite 46 years passing since initial assessment, JECFA’s ADI remains marked “TEMPORARY.” This indicates the initial evaluation was not considered definitive even then.

Is E557 Safe? The Regulatory Contradiction Question

E557 presents a fundamental regulatory paradox: opposite safety conclusions.

Regulatory Question	FDA Answer	EU/EFSA Answer	Implication
Is E557 safe for food?	NO – BANNED	YES – APPROVED	Fundamental disagreement
Has safety been fully assessed?	Implicitly yes (enough to ban)	NO – more data needed	Contradictory conclusions
What about genotoxicity?	Insufficient for food approval	Additional testing requested	Assessment incomplete
Is the JECFA ADI definitive?	No – too limited	Still temporary (46 years)	Provisional status

⚠️ UNPRECEDENTED DIVERGENCE: E557 represents one of the clearest examples of fundamental regulatory disagreement. FDA and EU regulatory agencies reached opposite conclusions about the same substance’s food safety. This suggests either:1. FDA is overly cautious (unnecessarily restrictive)
2. EU is insufficiently cautious (inadequately protective)
3. Assessment frameworks differ fundamentally
4. Data gaps prevent definitive conclusionsThe truth is likely combination of all three.

The Bottom Line

E557 is approved in EU but banned in USA — a rare example of fundamental international regulatory disagreement with incomplete assessment on both sides.

Key facts about E557:

– EU status: Officially approved for food coloring
– USA status: Explicitly BANNED for food use
– EFSA status: Approval incomplete; additional testing requested
– JECFA status: ADI provisional since 1979 (46 years unresolved)
– Genotoxicity: Additional in vivo testing requested
– Subchronic toxicity: Additional studies needed
– Bioavailability: Low absorption; minimal health accumulation concern
– Manufacturing concern: Potential for heavy metal contamination if not properly purified

🚨 BOTTOM LINE: E557 (Iron Oxide Red / E172(ii)) is officially approved as a food colorant in the EU but EXPLICITLY BANNED from human food consumption in the USA. EFSA’s approval is incomplete, with requests for additional genotoxicity and toxicity testing. JECFA’s temporary ADI from 1979 has never been finalized. This represents perhaps the most striking example of international regulatory divergence on food additive safety. Consumers in EU may be exposed to E557 in candies and supplements; consumers in USA cannot legally be sold E557-colored foods. The fundamental disagreement between regulatory agencies suggests neither assessment is definitive.

Final Thoughts: When Regulatory Systems Fundamentally Disagree

E557 is unique among problematic food additives because it reveals a fundamental split in global food safety regulation.

How E557 differs from the aluminum additives (E554, E555, E556):

E554, E555, E556 are problematic due to aluminum exposure concerns recognized across jurisdictions. Everyone agrees there’s a problem; they disagree on severity. E557 is different: FDA and EU fundamentally disagree about whether E557 is safe at all for food ingestion.

What E557 reveals about food safety systems:

– Regulatory agencies can reach opposite conclusions from the same substance
– Safety assessments are not universal; they reflect national risk philosophies
– Temporary/provisional statuses can persist for decades (JECFA 46 years)
– “Approved” doesn’t mean “fully assessed”; gaps can remain indefinitely
– International consumers have fundamentally different exposures to the same additive
– Incomplete data doesn’t automatically trigger rejection (EU approves despite gaps)

Why FDA banned and EU approved:

FDA perspective: “We don’t have enough evidence of safety, safer alternatives exist, processing poses occupational risks, contamination risks exist. Ban it.”

EU perspective: “We have adequate evidence of safety at reasonable exposure levels. Approve it.”

Both approaches have merit. FDA’s approach is conservative (protect against unknown risk). EU’s approach is pragmatic (approve with evidence of safety even if incomplete).

Consumer implications:

– If you live in USA: E557 is not in your foods (FDA banned it)
– If you live outside USA (especially EU): E557 may be in candies, supplements
– Neither conclusion is definitive due to incomplete assessment
– If you want to avoid E557, it’s already banned in USA; in EU, check labels for E172
– The disagreement suggests caution warranted, but not panic

The bigger picture: E557 demonstrates that global food safety is not monolithic. The same substance can be banned in one regulatory jurisdiction and approved in another. This reflects different risk tolerance, assessment philosophies, and political/economic interests. It also reveals that no single regulatory agency has “the right answer” — they’re all making judgments under uncertainty. Consumers deserve to understand these international differences.

What is E557? – Complete guide to understanding Iron Oxide Red